The responding officer and two witnesses, which were just a little ways behind her declared that she was not at fault

That's plainly a ludicrous conclusion. Of course she was at fault. She was following too closely to keep from rear-ending the other vehicle. That the road was snowy/icy simply means that she should have left additional room between her car and the vehicle in front of her.

bamr913:

Now shes being sued

"Being sued"? Since you said a trial occurred, I assume you mean that she was sued.

bamr913:

The first trial found her at 90% fault, so we filed an appeal.

"First trial"? Was there more than one? "We filed an appeal"? Unless you were also a party to the lawsuit, "we" did no such thing. Only she could have appealed. On what basis did she appeal? And why didn't your girlfriend's insurer simply pay the other driver's claim?

bamr913:

Any advice would be greatly appreciated.

The rules of this site prohibit giving legal advice, and I can't comment any further without knowing the basis on which your girlfriend is appealing. As you probably can discern, I doubt your girlfriend has any basis on which to appeal. While reasonable minds might differ about the percentage of fault attributable to your girlfriend and the other driver, there is no question that she is primarily at fault for following too closely, even if the other driver stopped suddenly in the middle of the highway for no good reason. Drivers are supposed to leave sufficient room to avoid a collision in such a situation.